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An uncharged atom of gold has an atomic number of 79 and an atomic mass of 197. this atom has ______ protons, ______ neutrons, and ______ electrons. an uncharged atom of gold has an atomic number of 79 and an atomic mass of 197. this atom has ______ protons, ______ neutrons, and ______ electrons. 276 . . . 118 . . . 79 118 . . . 79 . . . 118 118 . . . 276 . . . 118 79 . . . 276 . . . 79 79 . . . 118 . . . 79

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The atomic number is 79, therefore the atoms have 79 protons in their nuclei. Since the atom is uncharged, the number of protons equals the number of electrons: 79 electrons. The atomic mass is number of protons + neutrons. Since atomic mass is 197, 197-79= 118 neturons

User Ketsia
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7 votes

Answer:

79 protons, 79 electrons and 118 neutrons

Step-by-step explanation:

Hi, the atomic number of an element is equal to the number of protons it has.

For gold (Au):
Protons_(Au)=79

If the atom is uncharged (and only if it is uncharged), the number of electrons it has is equal to the number of protons.

For gold (Au):
Electrons_(Au)=79

At last, the atomic mass represents the protons plus the neutrons an atom has in its core. So:


Neutrons_(Au) + Protons_(Au)=197


Neutrons_(Au)=197 - 79


Neutrons_(Au)=118

User Abe Voelker
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